Abstract The mooring of the Third French Republic, at the beginning of the 1880s, depended as much on the will of the Opportunistes—for the most part men linked to Gambetta—as on the Modérés, given that colonial expansionism represented a neutral terrain on which these men could meet. The local level, that of the petites patries, here Lyon, provides a methodological space to attempt to understand how this République des hommes d’affaires, to use Jean Garigue’s expression, constructed both the French Imperial project and the way to run this project. It allows us also to understand how the liberal lyonnaises elites—mercantile, industrial, and financial—played a role in shaping its economic implantation in Indochina, particularly in Tonkin and Annam. At the turn of the century, a small nebula of patrons and local politiques, of national and imperial dimension, gathered around Ulysse Pila—the Lyonnais paragon of colonization in East Asia and Southeast Asia—played a crucial role in the first phase of Indochinese industrialization. Their dynamism reveals a play which can be read on three levels: local (Lyon/Tonkin), national (France/Indochina), and international (Colonial empire/East Asia and Southeast Asia). More than a mere form of municipal imperialism, their commitment, both financial and ideological, allows the elucidation of a constructive network of the French patronat, on the eve of the Belle Époque.